Question

In a survey of market, it is found that 143 persons use white toothpaste and 135 use red toothpaste. If 70 of them use both the toothpaste then find the number of persons who use at least one of the toothpaste​

Answer 1

let W and R represent white toothpaste and red toothpaste represently

n(W)=143

n(R)=135

n(WnR)=70

n( WuR)=?

Now,

n(WuR)=n(W)+n(R)_n(WnR)

=143+135_70

=208

that's all don't forget to write therefore.